pgsql: Avoid using internal test methods in SSL tests

Avoid using internal test methods in SSL tests

The SSL tests for pg_ctl restart with an incorrect key passphrase used
the internal _update_pid method to set the pidfile after running pg_ctl
manually instead of using the supplied ->restart method. This refactors
the ->restart method to accept a fail_ok parameter like how ->start and
->stop does, and changes the SSL tests to use this instead. This removes
the need to call internal test module functions.

Reviewed-by: Melih Mutlu 
Reviewed-by: Heikki Linnakangas 
Discussion: https://postgr.es/m/F81643C4-D7B8-4C6B-AF18-B73839966279@yesql.se

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/33774978c78175095da9e6c276e8bcdb177725f8

Modified Files
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src/test/perl/PostgreSQL/Test/Cluster.pm | 31 +++++++++++++++++++++++--------
src/test/ssl/t/001_ssltests.pl           | 23 +++++++++--------------
2 files changed, 32 insertions(+), 22 deletions(-)